#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=400;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
LL a[maxn],b[maxn],c[maxn];
int main(void)
{
  cin.tie(0);std::ios::sync_with_stdio(false);
  LL x1,y1,x2,y2;cin>>x1>>y1>>x2>>y2;
  LL n;cin>>n;
  for(LL i=1;i<=n;i++){
     cin>>a[i]>>b[i]>>c[i];
  }
  LL ans=0;
  for(LL i=1;i<=n;i++){
        LL t1=x1*a[i]+y1*b[i]+c[i];
        LL t2=x2*a[i]+y2*b[i]+c[i];
        if(t1>0&&t2<0) ans++;
        else if(t1<0&&t2>0) ans++;
  }
  cout<<ans<<"\n";
return 0;
}
